Pneumatic tube system with a long driving section and for high speed of the carriers



PNEUMATIC TUBE SYS'IEM BUCHWALD WITH A LONG DRIVING SECTION AND FOR HIGH SPEED OF THE CARRIERS Filed June 18, 1965 INVENTOR F BUG HWALD Mat-4% ATTORNEY United States Patent Ofifice 3,305,191 PNEUMATIC TUBE SYEZTEM WITH A LONG DRIV- ING SECTION AND FOR HIGH SPEED OF THE CARRIERS Fritz Buchwald, Berlin, Germany, assignor to International Standard Electric Corporation, New York, N.Y., a corporation of Delaware Filed June 18, 1965, Ser. No. 464,925 Claims priority, application Germany, June 29, 1964, St 22,318 6 Claims. (Cl. 243-4) In order to obtain in a pneumatic tube system with a long driving route high speed of the dispatch carriers the driving tube section is subdivided into several partial routes, at the ends of which the operating air is supplied in such a way that it becomes solely or preferably effective in the partial route section in which the carrier is in that moment. Thus each partial route represents a pneumatic separate system, operated by pressing or suction air or by both types of operating air.

In the arrangement of this kind known to the art said partial routes are separated by sluices. The dispatch carrier therefore passes through such a sluice before entering another partial route. But thereby no high speed of the dispatch carriers can be obtained because said carriers are stopped in the sluices or their speed is reduced, at least. In another arrangement known to the art the sluices are replaced by locking slides, whereby the operating air is reversed at the ends of the respective partial route. These slides are only opened for letting pass the dispatch carrier which needs not to be stopped. This arrangement enables to increase the speed of the dispatch carrier, but requires a considerable expenditure in components and system parts. Moreover, the failure of a locking slide can ensue a destruction of the system, if a dispatch carrier hits with high speed on a slide, having been not opened at all or is open only to a part.

The invention relates to a pneumatic tube system for high speed of the dispatch carrier and a long driving route, subdivided pneumatically into individual partial routes, at the end of which the operating air is eifective, so that the air becomes solely or preferably effective in the respective partial route in which a dispatch carrier is at that moment. Thereby sluices and locking slides as well as other lockings of the drive tube should be avoided.

The invention consists in that the drive tube is connected to the operating air supply respectively to the surrounding atmosphere via valves, controlled by the moving dispatch carrier, so that the high speed is obtained only in that drive tube section in which the dispatch carrier is at the moment.

A common blower is suitably provided for the supply of operating air, which is connected with the valves, leading to the drive tube through separate tube lines or pipes. This air is particularly suitable for systems to be newly installed, because the separate line can be installed. simultaneously with the drive tube. In older systems it would be more favourable in some cases to provide at the end of each partial route a separate blower. If separate tubes for the operating air and a common blower is provided, the diameter of the tubes must be so large that the line represents only a negligible resistance for the operating air. The blower can be a suction type or a compression type blower, it is also possible to use blowers of both kinds with a separate tube for each operating phase.

The invention is now explained with reference to an example, wherein a single suction-air blower is used.

The drawing 1 represents the drive tube, in which the dispatch carrier is moved from left to right. The

3,305,191 Patented Feb. 21, 1967 drive tube starts at a dispatching station not shown on the drawing and in a receiving station also not shown to which a sluice route can precede. The separate tube line 3 for the operating air is connected with the blower 4 approximately in the centre of its entire length. The drive tube 1 transits into a braking route 2, shortly before reaching the receiving station which is bridged by a tube line 6. -In said line 6 a blower 5, stable in its speed, is inserted and the line branches off shortly before the receiving station and enters the connecting tube 7 at the end of the last partial route which is also in connection with the operating air tube 3. The partial routes 8, 9, 10, and 14 are connected with the tube 3 at their front ends via valves 11, 21, 31, and 41. In the connecting line 7 and the rear end of the last partial route 14 no such valve is provided. These valves are controlled electro-magnetically by a system not shown on the drawing which system is again actuated by the indicators 13, 23, 33, 43, and 53. At the same spot at which the valve lines enter from the tube 3 the drive tube 1 further control valves 12, 22, 32, 42 are provided which lead to the surrounding atmosphere.

The system operates as follows: Both blowers operate and the air in the system is correspondingly pretensioned. The valves 11, 21, 31, 41 are open, the valves 12, 22, 32, 42 are closed. The dispatch carrier inserted into the drive tube on the left end is moved by the suction air in the direction of the arrow and bypasses at first the indicating device 13. Now valve 11 is closed and valve 12 opens. The suction air current enters essentially through the valve 12 and moves the carrier in the driving direction till it has reached the indicating device 23. Now valve 21 closes and valve 22 opens so that the suction air current becomes elfective through said valve. When the dispatch carrier has reached the indicating device 33 valve 31 is closed and valve 32 opens. When passing through the indicating device 53 the system is switched back to the original condition, i.e. the valves 11, 21, 31, 41 open and the valves 12, 22, 32, 42 close and the system can be used to dispatch another carrier. The first carrier enters into the braking section 2 equipped with the speed-stabilising blower 5 in which an essentially lower current speed prevails. It finally takes this speed and enters into the receiving station at a correspondingly reduced speed. When dispatching a carrier by a dispatching station, not shown on the drawing, into the drive tube sections 8, 9, 10, or 14, the valves switch into the same condition as when the carrier would pass over the indicating devices 13, 23, 33 or 43, located in front of said respective section.

The indicating devices 13, 23, 33, 43, and 53 are simple drive tube contacts. Due to the high speed with which the system operates it is recommended to use devices which are not equipped with contacts to be mechanically actuated by the dispatch carrier. Such devices are for example light bars or magnetic indicators.

What is claimed is:

1. A pneumatic tube system, comprising:

an extended, unobstructed drive tube for the transport of dispatch carriers;

a source of operating air, coupled to said drive tube, having air-moving power of a magnitude less than that required to said drive tube;

ports disposed at spaced points along said drive tube;

valves associated with each of said ports, sequentially operable, to control passage of air through said ports; and

control means coupled to said valves to actuate said valves sequentially, said control means being responsive to the movement of said carrier along said drive tube.

propel a carrier the full length of.

3 2. A pneumatic tube system, according to claim 1, wherein:

said drive tube is sectioned; said ports comprise a plurality of air pipes one each located at the end of each of said drive tube sections; said valves comprise a first plurality of air valves, one of each valve of said first plurality of valves being coupled to each said air pipe, and a second plurality of air valves interposed between said drive tube and said operating air source; and said control means comprises indicating devices, re-

sponsive to the disposition of dispatch carriers in said drive tube, coupled to said first and second plurality of air valves to control the operation of same. 3. A pneumatic tube system, according to claim 1, wherein:

said source of operating air supplies compressed air to said drive tube. 4. A pneumatic tube system, according to claim 1, wherein:

said source of operating air is an air-vacuum device which extracts air from said drive tube.

5. A pneumatic tube system, according to claim 1,

further comprising:

a braking section, connected to the terminal end of said drive tube, in which dispatch carrier speed is reduced.

6. A pneumatic tube system, according to claim 5,

wherein:

said braking section includes an air line bridged across and through-connected with said drive tube having an air-impeller device coupled thereto.

References Cited by the Examiner UNITED STATES PATENTS 623,509 4/1899 Bastedo 2436 1,753,987 4/1930 Hohne 2436 3,237,881 3/1966 Grosswiller 2437 FOREIGN PATENTS 11,966 6/ 1892 Great Britain.

EVON C. BLUNK, Primary Examiner.

H. C. HORNSBY, Assistant Examiner. 

1. A PNEUMATIC TUBE SYSTEM, COMPRISING: AN EXTENDED, UNOBSTRUCTED DRIVE TUBE FOR THE TRANSPORT OF DISPATCH CARRIERS; A SOURCE OF OPERATING AIR, COUPLED TO SAID DRIVE TUBE, HAVING AIR-MOVING POWER OF A MAGNITUDE LESS THAN THAT REQUIRED TO PROPEL A CARRIER THE FULL LENGTH OF SAID DRIVE TUBE; PORTS DISPOSED AT SPACED POINTS ALONG SAID DRIVE TUBE; VALVES ASSOCIATED WITH EACH OF SAID PORTS, SEQUENTIALLY OPERABLE, TO CONTROL PASSAGE OF AIR THROUGH SAID PORTS; AND CONTROL MEANS COUPLED TO SAID VALVES TO ACTUATE SAID VALVES SEQUENTIALLY, SAID CONTROL MEANS BEING RESPONSIVE TO THE MOVEMENT OF SAID CARRIER ALONG SAID DRIVE TUBE. 